Gemstone



FIG. 1 is a top perspective view of a gemstone, showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a front elevational view thereof, the rear, left, and right elevational views being identical thereto;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

CLAIM The ornamental design for a gemstone, as shown and described. 